Abstract Pediatric AIDS remains a public health emergency in Zambia, with the majority of new infections resulting from perinatal transmission. Early infant diagnosis (EID), timely initiation of antiretroviral therapy (ART), and effective long-term clinical follow-up are critical to programmatic success and to saving the lives of HIV-infected children. In Zambia, the current standard for diagnosis of infant infection is HIV DNA PCR, performed at one of only three reference laboratories in the country. High clinical volume and long specimen transport times can result in diagnostic delays of many weeks, and this is believed to contribute to substantial program attrition and poor clinical outcomes. We propose a randomized, controlled trial of a new point-of-care (POC) technology for early infant HIV diagnosis, developed at the University of Cambridge, U.K. We will introduce the Simple AMplification-Based Assay (SAMBA) in 2 postnatal facilities in Lusaka, Zambia, where the standard of care is to offer off-site DNA PCR to all HIV-exposed children at 6 weeks of life. Eligible, HIV-exposed infants will be randomly assigned to SAMBA same-day infant diagnosis or the current standard of care. Our primary outcome will be the proportion of HIV-infected children in each study arm who commence antiretroviral therapy within 12 weeks of the diagnostic specimen being drawn. Our secondary outcomes will include: 1) a comparison of time to ART initiation in each study arm, 2) the proportion of HIV-exposed children who remain in care at 6 months of life (stratified by HIV status), and 3) feasibility of the SAMBA technology in our setting. 2